Nong-O Gaiyanghadao

Nong-O Sit Or (น้องโอ๋ ศิษย์ อ.) was born as Apichet Khotanan in Sakon Nakhon Province in the Northeastern (Isan) region of Thailand. He had his first fight at the age of 9. He became interested in Muay Thai when he saw one of his neighbors training. Nong-O was invited to train, and after a month of training he had his first fight.[3]

On August 3, 2008, Nong-O fought against Kōji Okuyama at Keio Plaza hotel in Hachiōji, Tokyo, and he won by KO with left elbow strike during 3rd round.[4] December 9, 2008, he fought against Wutidet Lukprabath at Lumpinee Stadium in the memorial event of Lumpinee Stadium establishment. He won by decision after five rounds.[5]

On January 18, 2009, Nong-O fought against Tomoaki Suehiro at Yoyogi National Gymnasium for the Muay Thai event Muay Lok. He won by TKO when the referee stopped the contest after he knocked Suehiro down twice with a right hook and left hook during first round. After the contest, he was given a bunch of flowers by Shinya Aoki. Nong-O was going to fight against Shunta Itō in the beginning, but he was replaced because his legs had not healed enough.[6]

On November 8, 2009, he fought against Trijak Sitjomtrai in Japan. Trijak was the current champion at featherweight sanctioned by the Professional Boxing Association of Thailand, but Nong-O won by majority decision (2-0) after five rounds.[7]

On December 8, Nong-O fought against Petboonchu F.A. Group for his Lumpinee Stadium title at Super featherweight (130 lbs). Nong-O won by decision and became the new champion.

On January 17, 2010, Nong-O participated in the tournament Yod Muay Champions Cup 60kg in Japan. He fought against Singdam Kiatmoo9 in the first match. After five rounds, the bout was declared a draw. Nong-O lost by the split decision after extra round (6th round).[8] On December 9, he challenged Saenchai's titles of Lumpinee Stadium and WMC, but he lost by decision.

On January 19, 2011, Nong-O Sit Or was named 2010 Boxer of the Year at the Society of Friends of Sportswriters Awards Night in Bangkok.[9]

Nong-O started the year with a win over Singdam in February and followed it up the following month with another win over F16 Rajanon. He then lost a very close fight to Singdam in May, which many thought Nong-O had done enough to win, but beat Petboonchu FA Group in June. On 31 July he fought Singdam in the main event at Lumpinee Stadium and was defeated by unanimous decision.[10]

He faced Petboonchu F.A. Group for the seventh time on October 12, 2012 at Rajadamnern Stadium.[11][12]

He TKO'd Mongkolchai Phetsupaphan in five on February 7, 2013.[13]

He beat Singdam Kiatmuu9 on points to win the Lumpinee lightweight belt on June 7, 2013.[14]

Following a competitive hiatus in which he moved to Singapore to coach at Evolve,[15] Nong-O returned in 2018 when ONE Championship unveiled their new striking format: the ONE Super Series. Nong-O debuted on April 20 at ONE Championship: Heroes of Honor and defeated Fabio Pinca via unanimous decision.[16] He returned to his Thai homeland in October at ONE Championship: Kingdom of Heroes, and defeated Mehdi Zatout via unanimous decision.[17]

On February 16, 2019, Nong-O defeated Han Zihao by unanimous decision to become the inaugural ONE Bantamweight Muay Thai World Champion at ONE Championship: Clash of Legends in Bangkok.[18]

On May 10, 2019, he would defend his ONE Bantamweight Muay Thai World Championship against Hiroaki Suzuki at ONE Championship: Warriors of Light, winning by unanimous decision and retaining his title.[19]

He made his second title defense against Brice Delval at ONE Championship: Immortal Triumph in Ho Chi Minh City on September 6, 2019, featuring ONE Championship's first event in Vietnam and first all-striking card, where he successfully retained the ONE Bantamweight Muay Thai World Championship via a closely contested split decision win.[20]

Nong-O successfully defended his ONE Bantamweight Muay Thai World Championship against Saemapetch Fairtex, winning by fourth-round knockout in a fight where he knocked down Saemapetch twice in the second round.[21]

After Alaverdi Ramazanov won the ONE Bantamweight Kickboxing World Championship at ONE Championship: Edge Of Greatness, he expressed interest in defending his title against Nong-O.[22] A title fight between the two was scheduled for ONE Championship: Heart of Heroes on March 20, 2020. However, the event was cancelled due to the COVID-19 pandemic.

Instead, Nong-O was scheduled to defend his ONE Bantamweight Muay Thai World Championship against Rodlek P.K. Saenchaimuaythaigym after the latter won the 2020 ONE Bantamweight Muay Thai Tournament at ONE Championship: A New Breed. He was scheduled to defend his title against Rodlek at ONE Championship: Collision Course on December 18, 2020.[23] He successfully defended his title with a third round knockout of Rodlek.[24]

Nong-O made his fifth title defense of the ONE Bantamweight Muay Thai World Championship against Felipe Lobo at ONE: X on March 26, 2022.[25] He won the bout after knocking out Lobo with an uppercut in the third round.[26]

Nong-O defended his ONE Bantamweight Muay Thai World Championship against Liam Harrison at ONE on Prime Video 1 on August 27, 2022.[27] He won the bout in the first round after Harrison was unable to continue due to leg kicks.[28]

Nong-O was scheduled to face former ONE Bantamweight Muay Thai World Champion Alaverdi Ramazanov for his seventh title defense on January 14, 2023, at ONE on Prime Video 6.[29] However, the bout was moved to headline at ONE Friday Fights 1 on January 20.[30] He won the bout via knockout in the third round.[31]

Nong-O faced against former ONE Flyweight Muay Thai World champion Jonathan Haggerty for his eighth title defense on April 22, 2023, at ONE Fight Night 9.[32] He lost the bout via knockout in the first round.[33]